1. Field of the Invention
This invention relates to supplying items such as tape cassettes from a master storage facility such as a tape library to an on-line storage facility that facilitates automatic feeding of the items to a processing station such as a station including one or more tape recorder/reproducers (VTRs) in a broadcast studio.
2. Description of the Prior Art
In television and other broadcasting it is common practice to piece together a program largely from prerecorded segments. These segments are recorded on separate tape cassettes and stored in a tape library. A television station scheduling department compiles a master list of events consisting of prerecorded segments and "live" segments or other "off-machine" events. The master list sets forth the events in a sequence from top to bottom and represents a program for broadcast.
Before broadcast of the program begins, the cassettes containing the segments to be broadcast early in the program are stored in an on-line storage facility or multi-cassette receiver. In combination with certain electromechanical apparatus, this facility feeds the cassettes automatically in proper sequence to one or more video tape recorders (VTRs) that reproduce the recorded signals for broadcast. After each segment is reproduced and broadcast, the tape cassette on which it is recorded is automatically returned to the on-line storage facility. Since the master list of events normally substantially exceeds the capacity of the on-line storage facility to store simultaneously the tape cassettes for a complete program, it is necessary to add new cassettes from the library that appear farther down the master list to the on-line storage facility as the program is broadcast. To make room for the new cassettes, it is necessary to withdraw cassettes that are already stored in the on-line storage facility.
In conventional practice, it is a problem to determine which cassettes to withdraw from the on-line storage facility in order to make room for new cassettes. Normally, some of the cassettes in the on-line storage facility need to be supplied to the VTR station more than once. Such cassettes may include commercials, program themes, important news stories, etc. Thus, it is not a solution simply to withdraw each cassette from the on-line storage facility as soon as it has returned from one trip to the VTR station. Other cassettes need to make only one trip to the VTR station, but to determine which cassettes fall into this category and to withdraw them without error and in a timely manner requires vigilance by the user of the system. The identity of each cassette in the on-line storage facility and its place on the master list needs to be checked carefully and repeatedly in order to avoid mistakes. Particularly if the user or operator of the system has other duties and cannot monitor the system continuously, this may present a serious problem.
Co-pending application Ser. No. 06/719,066, filed Apr. 2, 1985 , now U.S. Pat. No. 4,644,425, and assigned to the assignee of the present application, discloses apparatus for automatically supplying tape cassettes from a multi-cassette receiver to cassette reproducing apparatus and the use of lights to signal proper reading of bar codes on the tape cassettes. Other automatic changers for cassette recording/reproducing apparatus. are disclosed in U.S. Pat. Nos. 3,825,949 and No. 3,879,758 to Pyles and U.S. Pat. No. 3,852,819 to Starr. None of these documents discloses a solution to the problems outlined above.